1. Field of the Invention
The present invention relates generally to bus plugs, and more particularly to bus plugs having an interlock mechanism for locking the bus plug on a busway.
2. Description of the Prior Art
Electrical power distribution systems often utilize plug-in busway comprising a generally rectangular cross section busway housing within which is carried a plurality of parallel bus bars which are the current conducting members.
Various electrical accessories such as fusable units, circuit breaker units, combination starter and contactor units, transformer units, capacitor units, and ground detector units, are provided in the form of plug-in units, commonly referred to simply as plugs or bus plugs, which plug into the busway thus providing quick, reliable and safe connection of the electrical accessory to the power conducting bus bars in the busway.
A typical busway and bus plug arrangement of the prior art is that shown in U.S. Pat. No. 3,339,038 to Jorgensen et al., and assigned to the assignee of the present invention.
The Jorgensen et al. patent discloses a bus plug having an interlock assembly for locking the bus plug to the busway. The interlock assembly prevents the bus plug from being connected to or disconnected from the busway when the electrical accessory contained within the bus plug is in an "On" position. It also prohibits the bus plug from being switched to an "On" position until the interlock assembly is moved to its locked position thus securely locking the bus plug in place on the busway.
While the Jorgensen et al. apparatus does successfully accomplish the functions just mentioned, and has been in use by the assignee of the present invention for many years, the interlock mechanism of the Jorgensen et al. apparatus is relatively complex and expensive to manufacture.